Out of these two types of ammo which is more accurate/better quality?

Both of them fall into the Plinking Ammo catagory. I wouldn't expect much less than 2" groups at 100 yards. Some folks swear to that MOA but I think there is some wishfull thinking going on. Talon has had a few quality contol issues with case sizing in the not too far distant past. They have assured us that it has been resolved, but there's always a chance of running across a can of the old stuff at a gunshow. Talon is simply US military surplus ammo that has been taken apart and then "remanufactured". Yugo is straight out of the can military surplus machinegun ammo. It has a bit more punch than Talon and is also smokier and a little on the dirty side. Keith Pagel did a little testing and has determined that Yugo is slightly corrosive. A good cleaning is in order just in case.

Does Yugo come packed in white cardboard boxes that come sealed, three boxes together, in a metalic plastic foil?

I think there is some out there that came packed that way. The easiest way to ID Yugo is the headstamp, that being IK and then the year.

Ironically, the stuff being imported by Mitchell's Mauser's is made at the same plant as the Yugo stuff. They say it's a lead core but a magnet will stick to it and at $3 a shot, they can keep it. I would spend the same money and get AMAX from The Hunting Shack, that way your getting a match round that really has a lead core.

As far as Talon goes, they say that they have solved their QC problems. It's good plinking ammo and should hold around 2 MOA, some guys have shot better but that's about avg. You have to remember that's it's made for the M2 and that disperses it's rounds into a beaten zone. As long as X amount hit the target the Military is happy.